BiwaScheme Blackboard http://blackboard.biwascheme.org/BiwaScheme Blackboard is a sandbox for BiwaScheme, a R6RS Scheme interpreter written in JavaScript. You can edit, run and save Scheme code in your browser.

Calico Scheme – IPRE Wiki http://calicoproject.org/Calico_SchemeCalico Scheme is a new implementation of a Scheme-based language for Calico. It implements many core Scheme functions, but also adds some functionality to bring it into line with the other modern languages like Python and Ruby.

http://www.dwheeler.com/readable/index.htmlMany people find Lisp s-expressions hard to read as a programming notation. I’ve developed Lisp programs for decades, and though I can read s-expressions well, I remain dissatisfied with their syntactic limitations.

M-expression – Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/M-expressionIn computer programming, M-expressions (or meta-expressions) were intended to be the expressions used to write functions in the Lisp programming language. Data to be manipulated using M-expressions was to be written using S-expressions. M-expressions were used for the original theoretical language in early papers about Lisp, but the first working implementation of Lisp interpreted encodings of M-expressions as S-expressions, and M-expressions were never actually implemented.